Yup. I'm linked to numerous accounts including EA, Steam and Microsoft etc. etc. just a whole spiderweb of my accounts. I did find however that watching Battlefield REDSEC on Twitch did gift me Twitch Drops. I was hoping by watching REDSEC, it would somehow "backfill" my old drops. Didn't work out.
The first set of Twitch drops note that you had until August 25th to "redeem" them. The second set note that you had until October 24th. I think at this point you gotta find someone working at EA-DICE that actually cares enough to go through your account and just toss them your way. I don't think the Twitch-BF6 app integration thing will backfill drops. Just gotta hope somebody sees our posts.